package com.kylin.common.core.util;

import com.alibaba.fastjson2.JSONObject;
import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.io.Serializable;
import java.nio.charset.StandardCharsets;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

/**
 * Created by lake on 17-4-12.
 */
public class RSACoder
{
    public static final String KEY_ALGORITHM = "RSA";

    public static final String SIGNATURE_ALGORITHM = "MD5withRSA";

    private static final String PUBLIC_KEY = "RSAPublicKey";

    private static final String PRIVATE_KEY = "RSAPrivateKey";

    public static byte[] decryptBASE64(String key)
    {
        return Base64.decodeBase64(key);
    }

    public static String encryptBASE64(byte[] bytes)
    {
        return Base64.encodeBase64String(bytes);
    }

    /**
     * 用私钥对信息生成数字签名
     *
     * @param data       加密数据
     * @param privateKey 私钥
     * @return
     * @throws Exception
     */
    public static String sign(byte[] data, String privateKey)
            throws Exception
    {
        // 解密由base64编码的私钥
        byte[] keyBytes = decryptBASE64(privateKey);
        // 构造PKCS8EncodedKeySpec对象
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        // KEY_ALGORITHM 指定的加密算法
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        // 取私钥匙对象
        PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);
        // 用私钥对信息生成数字签名
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initSign(priKey);
        signature.update(data);
        return encryptBASE64(signature.sign());
    }

    /**
     * 校验数字签名
     *
     * @param data      加密数据
     * @param publicKey 公钥
     * @param sign      数字签名
     * @return 校验成功返回true 失败返回false
     * @throws Exception
     */
    public static boolean verify(byte[] data, String publicKey, String sign) throws Exception
    {
        // 解密由base64编码的公钥
        byte[] keyBytes = decryptBASE64(publicKey);
        // 构造X509EncodedKeySpec对象
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
        // KEY_ALGORITHM 指定的加密算法
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        // 取公钥匙对象
        PublicKey pubKey = keyFactory.generatePublic(keySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initVerify(pubKey);
        signature.update(data);
        // 验证签名是否正常
        return signature.verify(decryptBASE64(sign));
    }

    public static byte[] decryptByPrivateKey(byte[] data, String key)
            throws Exception
    {
        // 对密钥解密
        byte[] keyBytes = decryptBASE64(key);
        // 取得私钥
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
        // 对数据解密
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        return cipher.doFinal(data);
    }

    /**
     * 解密<br>
     * 用私钥解密
     *
     * @param data
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] decryptByPrivateKey(String data, String key)
            throws Exception
    {
        return decryptByPrivateKey(decryptBASE64(data), key);
    }

    /**
     * 解密<br>
     * 用公钥解密
     *
     * @param data
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] decryptByPublicKey(byte[] data, String key)
            throws Exception
    {
        // 对密钥解密
        byte[] keyBytes = decryptBASE64(key);
        // 取得公钥
        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key publicKey = keyFactory.generatePublic(x509KeySpec);
        // 对数据解密
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.DECRYPT_MODE, publicKey);
        return cipher.doFinal(data);
    }

    /**
     * 加密<br>
     * 用公钥加密
     *
     * @param data
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPublicKey(String data, String key)
            throws Exception
    {
        // 对公钥解密
        byte[] keyBytes = decryptBASE64(key);
        // 取得公钥
        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key publicKey = keyFactory.generatePublic(x509KeySpec);
        // 对数据加密
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        return cipher.doFinal(data.getBytes());
    }

    /**
     * 加密<br>
     * 用私钥加密
     *
     * @param data
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPrivateKey(byte[] data, String key)
            throws Exception
    {
        // 对密钥解密
        byte[] keyBytes = decryptBASE64(key);
        // 取得私钥
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
        // 对数据加密
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, privateKey);
        return cipher.doFinal(data);
    }

    /**
     * 取得私钥
     *
     * @param keyMap
     * @return
     * @throws Exception
     */
    public static String getPrivateKey(Map<String, Key> keyMap)
    {
        Key key = keyMap.get(PRIVATE_KEY);
        return encryptBASE64(key.getEncoded());
    }

    /**
     * 取得公钥
     *
     * @param keyMap
     * @return
     * @throws Exception
     */
    public static String getPublicKey(Map<String, Key> keyMap)
    {
        Key key = keyMap.get(PUBLIC_KEY);
        return encryptBASE64(key.getEncoded());
    }

    /**
     * 初始化密钥
     *
     * @return
     * @throws Exception
     */
    public static Map<String, Key> initKey()
            throws Exception
    {
        KeyPairGenerator keyPairGen = KeyPairGenerator
                .getInstance(KEY_ALGORITHM);
        keyPairGen.initialize(2048);
        KeyPair keyPair = keyPairGen.generateKeyPair();
        Map<String, Key> keyMap = new HashMap(2);
        // 公钥
        keyMap.put(PUBLIC_KEY, keyPair.getPublic());
        // 私钥
        keyMap.put(PRIVATE_KEY, keyPair.getPrivate());
        return keyMap;
    }

    public static void main(String args[])
    {
        Serializable id = 1L;
        System.out.println(id.toString());
        Long ids = 1L;
        System.out.println(id.toString().equals(ids.toString()));
        Map<String, Key> keyMap = null;
        try
        {

            String publicKey = "MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA02HzJQU4PkGwjr9MStvG\n" +
                    "3hx5PR79CjxMi3OCn+yhA4pT20f+yqAPNdjdztO75bO+eMPYUNp+MCuYMFpHWV0S\n" +
                    "kYldfBb25rA5dSoUdAWoOdsZ2veN1A1fxyw6AWW8lICUeUMzdQAzoED0Cz4srD3M\n" +
                    "AaNVmLX6+jEX364hDxhNB5eWUV/W9mGO0+RVcn+FM2XKm5J7iajQQ6WkQEn34tnA\n" +
                    "HWDzTPauCQJFgEIFBhUCUqkWxmJ/0jMWPWAjSxntk/xX/j9I1lobJXk9dUi6iOvz\n" +
                    "dTTbbZl+YJCw44Q1XVq+dqI5P4kqgH9xMvZAahW5bjbUq1ttupK6dg+YwemyBe/i\n" +
                    "Fe3hMUU/lcwEM8Yc+HFB4a9RSYSQhfPUaEL3qcsAmOt4YUSQhTm3GCTsrwGZXjej\n" +
                    "vV+DeEMglYY4nxTweEtN3PB71ZNUDiXd2ENbWzjJ22bFk4Je5drAGBsH5R9HTOJB\n" +
                    "efXAEyrEjn3GVt6+eakysO2ckK9RnhxzDWMrUrns7mq/u1GX7I19ulDTJXFPnWK3\n" +
                    "nXs4tluGDIaRizdWw4ehVwtlCuOCPIKD5yJggBJHRySGRtTRVXiZLjxUJ4zX2VnF\n" +
                    "co796EnJ2tlnrZwizGLCocIXPfEC/6os0R6q7MCW/7r0Gdr2+Pq8+hYMf4XbQI0J\n" +
                    "+8vVUd4kymioN3A4AZCTu0cCAwEAAQ==";

            JSONObject pa = new JSONObject();
            pa.put("timestamp", "1684024606726");
            String s = new String(encryptByPublicKey(encryptBASE64(pa.toString().getBytes(StandardCharsets.UTF_8)),publicKey), StandardCharsets.UTF_8);
            System.out.println(s);
//            keyMap = RSACoder.initKey();
//            String publicKey = RSACoder.getPublicKey(keyMap);
//            String privateKey = RSACoder.getPrivateKey(keyMap);
//
//            System.err.println("公钥: \n\r" + publicKey);
//            System.err.println("私钥： \n\r" + privateKey);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }


    }
}